Spec docs for IDNA2008 support

[exim.git] / doc / doc-txt / OptionLists.txt

diff --git a/doc/doc-txt/OptionLists.txt b/doc/doc-txt/OptionLists.txt
index 21fd0fa26e3c61ff33f843ad451bcae12b884384..fc528518d0d72ce8ad74b56b3829c9bccf6a0903 100644 (file)
--- a/doc/doc-txt/OptionLists.txt
+++ b/doc/doc-txt/OptionLists.txt
@@ -48,12 +48,14 @@ release 4.00, and so no router options are shown as earlier than 4.00, though
 in fact some of them were inherited from earlier versions.
 
 -----------------------------------------------------------------------------------------
 in fact some of them were inherited from earlier versions.
 
 -----------------------------------------------------------------------------------------

-accept_8bitmime                      boolean         false         main              1.60
+accept_8bitmime                      boolean         true          main              1.60 changed to true in 4.80

 acl_not_smtp                         string*         unset         main              4.11
 acl_not_smtp_mime                    string*         unset         main              4.51 with content scan
 acl_smtp_auth                        string*         unset         main              4.00
 acl_smtp_connect                     string*         unset         main              4.11
 acl_smtp_data                        string*         unset         main              4.00
 acl_not_smtp                         string*         unset         main              4.11
 acl_not_smtp_mime                    string*         unset         main              4.51 with content scan
 acl_smtp_auth                        string*         unset         main              4.00
 acl_smtp_connect                     string*         unset         main              4.11
 acl_smtp_data                        string*         unset         main              4.00

+acl_smtp_data_prdr                   string*         unset         main              4.82 with experimental_prdr
+acl_smtp_dkim                        string*         unset         main              4.70 unless disable_dkim

 acl_smtp_etrn                        string*         unset         main              4.00
 acl_smtp_expn                        string*         unset         main              4.00
 acl_smtp_helo                        string*         unset         main              4.20
 acl_smtp_etrn                        string*         unset         main              4.00
 acl_smtp_expn                        string*         unset         main              4.00
 acl_smtp_helo                        string*         unset         main              4.20


@@ -171,10 +173,15 @@ directory_transport                  string*         unset         redirect
 disable_ipv6                         boolean         false         main              4.61
 disable_logging                      boolean         false         routers           4.11
                                                      false         transports        4.11
 disable_ipv6                         boolean         false         main              4.61
 disable_logging                      boolean         false         routers           4.11
                                                      false         transports        4.11

+dmarc_forensic_sender                string          unset         main              4.82 if experimental_dmarc
+dmarc_history_file                   string          unset         main              4.82 if experimental_dmarc
+dmarc_tld_file                       string          unset         main              4.82 if experimental_dmarc

 dns_again_means_nonexist             domain list     unset         main              1.89
 dns_check_names_pattern              string          +             main              2.11
 dns_csa_search_limit                 integer         5             main              4.60
 dns_csa_use_reverse                  boolean         true          main              4.60
 dns_again_means_nonexist             domain list     unset         main              1.89
 dns_check_names_pattern              string          +             main              2.11
 dns_csa_search_limit                 integer         5             main              4.60
 dns_csa_use_reverse                  boolean         true          main              4.60

+dns_dnssec_ok                        integer         -1            main              4.82
+dns_dane_ok                          integer         -1            main              4.83

 dns_ipv4_lookup                      boolean         false         main              3.20
 dns_qualify_single                   boolean         true          smtp
 dns_retrans                          time            0s            main              1.60
 dns_ipv4_lookup                      boolean         false         main              3.20
 dns_qualify_single                   boolean         true          smtp
 dns_retrans                          time            0s            main              1.60


@@ -186,6 +193,7 @@ driver                               string          unset         authenticator
                                                      unset         routers           4.00
                                                      unset         transports
 drop_cr                              boolean         false         main              4.00 became a no-op in 4.21
                                                      unset         routers           4.00
                                                      unset         transports
 drop_cr                              boolean         false         main              4.00 became a no-op in 4.21

+dscp                                 string          unset         smtp              4.82

 dsn_from                             string*         +             main              4.67
 envelope_to_add                      boolean         false         transports
 envelope_to_remove                   boolean         true          main
 dsn_from                             string*         +             main              4.67
 envelope_to_add                      boolean         false         transports
 envelope_to_remove                   boolean         true          main


@@ -233,6 +241,7 @@ forbid_include                       boolean         false         redirect
 forbid_pipe                          boolean         false         redirect          4.00
 forbid_sieve_filter                  boolean         false         redirect          4.44
 forbid_smtp_code                     boolean         false         redirect          4.63
 forbid_pipe                          boolean         false         redirect          4.00
 forbid_sieve_filter                  boolean         false         redirect          4.44
 forbid_smtp_code                     boolean         false         redirect          4.63

+force_command                        boolean         false         pipe              4.82

 freeze_exec_fail                     boolean         false         pipe              1.89
 freeze_signal                        boolean         false         pipe              4.75
 freeze_tell                          boolean         false         main              4.00 replaces freeze_tell_mailmaster
 freeze_exec_fail                     boolean         false         pipe              1.89
 freeze_signal                        boolean         false         pipe              4.75
 freeze_tell                          boolean         false         main              4.00 replaces freeze_tell_mailmaster


@@ -240,13 +249,14 @@ from                                 string*         unset         autoreply
 gecos_name                           string*         unset         main
 gecos_pattern                        string          unset         main
 gethostbyname                        boolean         false         smtp
 gecos_name                           string*         unset         main
 gecos_pattern                        string          unset         main
 gethostbyname                        boolean         false         smtp

+gnutls_allow_auto_pkcs11             boolean         false         main              4.82

 gnutls_compat_mode                   boolean         unset         main              4.70
 gnutls_compat_mode                   boolean         unset         main              4.70

-gnutls_require_kx                    string*         unset         main              4.67
-                                     string*         unset         smtp              4.67
-gnutls_require_mac                   string*         unset         main              4.67
-                                     string*         unset         smtp              4.67
-gnutls_require_protocols             string*         unset         main              4.67
-                                     string*         unset         smtp              4.67
+gnutls_require_kx                    string*         unset         main              4.67 deprecated, warns
+                                     string*         unset         smtp              4.67 deprecated, warns
+gnutls_require_mac                   string*         unset         main              4.67 deprecated, warns
+                                     string*         unset         smtp              4.67 deprecated, warns
+gnutls_require_protocols             string*         unset         main              4.67 deprecated, warns
+                                     string*         unset         smtp              4.67 deprecated, warns

 group                                string          +             routers           4.00
                                                      unset         transports        4.00 replaces local option in some transports
 header_line_maxsize                  integer         0 (unset)     main              4.14
 group                                string          +             routers           4.00
                                                      unset         transports        4.00 replaces local option in some transports
 header_line_maxsize                  integer         0 (unset)     main              4.14


@@ -286,9 +296,12 @@ hosts_override                       boolean         false         smtp
 hosts_randomize                      boolean         false         manualroute       4.00
                                                      false         smtp              3.14
 hosts_require_auth                   host list       unset         smtp              4.00
 hosts_randomize                      boolean         false         manualroute       4.00
                                                      false         smtp              3.14
 hosts_require_auth                   host list       unset         smtp              4.00

+hosts_require_ocsp                   host list       unset         smtp              4.82 if experimental_ocsp

 hosts_require_tls                    host list       unset         smtp              3.20
 hosts_treat_as_local                 domain list     unset         main              1.95
 hosts_try_auth                       host list       unset         smtp              4.00
 hosts_require_tls                    host list       unset         smtp              3.20
 hosts_treat_as_local                 domain list     unset         main              1.95
 hosts_try_auth                       host list       unset         smtp              4.00

+hosts_try_fastopen                   host list       unset         smtp              4.88
+hosts_try_prdr                       host list       unset         smtp              4.82 if experimental_prdr

 ibase_servers                        string          unset         main              4.23
 ignore_bounce_errors_after           time            0s            main              4.00
 ignore_eacces                        boolean         false         redirect          4.00
 ibase_servers                        string          unset         main              4.23
 ignore_bounce_errors_after           time            0s            main              4.00
 ignore_eacces                        boolean         false         redirect          4.00


@@ -336,7 +349,7 @@ mailbox_size                         string*         unset         appendfile
 maildir_format                       boolean         false         appendfile        1.70
 maildir_retries                      integer         10            appendfile        1.70
 maildir_tag                          string*         unset         appendfile        1.92
 maildir_format                       boolean         false         appendfile        1.70
 maildir_retries                      integer         10            appendfile        1.70
 maildir_tag                          string*         unset         appendfile        1.92

-maildir_use_size_file                boolean         false         appendfile        4.30
+maildir_use_size_file                boolean*        false         appendfile        4.30 expanded in 4.77

 maildirfolder_create_regex           string          unset         appendfile        4.62
 mailstore_format                     boolean         false         appendfile        2.00
 mailstore_prefix                     string*         unset         appendfile        2.00
 maildirfolder_create_regex           string          unset         appendfile        4.62
 mailstore_format                     boolean         false         appendfile        2.00
 mailstore_prefix                     string*         unset         appendfile        2.00


@@ -373,7 +386,7 @@ once                                 string*         unset         autoreply
 once_file_size                       integer         0             autoreply         3.20
 once_repeat                          time            0s            autoreply         2.95
 one_time                             boolean         false         redirect          4.00
 once_file_size                       integer         0             autoreply         3.20
 once_repeat                          time            0s            autoreply         2.95
 one_time                             boolean         false         redirect          4.00

-openssl_options                      string "+dont_insert_empty_fragments" main      4.73
+openssl_options                      string          +no_sslv2     main              4.73 default changed in 4.80

 optional                             boolean         false         iplookup          4.00
 oracle_servers                       string          unset         main              4.00
 owners                               string list     unset         redirect          4.00
 optional                             boolean         false         iplookup          4.00
 oracle_servers                       string          unset         main              4.00
 owners                               string list     unset         redirect          4.00


@@ -393,6 +406,7 @@ pipelining_advertise_hosts           host list       "*"           main
 port                                 integer         0             iplookup          4.00
                                      string          "smtp"        smtp
 preserve_message_logs                boolean         false         main
 port                                 integer         0             iplookup          4.00
                                      string          "smtp"        smtp
 preserve_message_logs                boolean         false         main

+prdr_enable                          boolean         false         main              4.82 if experimental_prdr

 primary_hostname                     string          +             main
 print_topbitchars                    boolean         false         main              1.89
 process_log_path                     string          unset         main              4.21
 primary_hostname                     string          +             main
 print_topbitchars                    boolean         false         main              1.89
 process_log_path                     string          unset         main              4.21


@@ -466,14 +480,19 @@ sender_unqualified_hosts             host list       unset         main
 senders                              address list    unset         routers           4.00
 serialize_hosts                      host list       unset         smtp              1.60
 server_advertise_condition           string*         unset         authenticators    4.14
 senders                              address list    unset         routers           4.00
 serialize_hosts                      host list       unset         smtp              1.60
 server_advertise_condition           string*         unset         authenticators    4.14

+server_channelbinding                bool            false         gsasl             4.80

 server_condition                     string*         unset         authenticators    3.10 (plaintext) 4.64 (others)
 server_condition                     string*         unset         authenticators    3.10 (plaintext) 4.64 (others)

-server_hostname                      string*   "$primary_hostname" cyrus_sasl        4.43
+server_hostname                      string*   "$primary_hostname" cyrus_sasl,gsasl,heimdal_gssapi (cyrus-only) 4.80 (others)
+server_keytab                        string*         unset         heimdal_gssapi    4.80

 server_mail_auth_condition           string*         unset         authenticators    3.22
 server_mail_auth_condition           string*         unset         authenticators    3.22

-server_mech                          string          public_name   cyrus_sasl        4.43
+server_mech                          string          public_name   cyrus_sasl,gsasl  4.43 (cyrus-only) 4.80 (others)
+server_password                      string          unset         gsasl             4.80

 server_prompts                       string*         unset         plaintext         3.10
 server_prompts                       string*         unset         plaintext         3.10

-server_realm                         string          unset         cyrus_sasl        4.43
+server_realm                         string          unset         cyrus_sasl,gsasl  4.43 (cyrus-only) 4.80 (others)
+server_scram_iter                    string*         unset         gsasl             4.80
+server_scram_salt                    string*         unset         gsasl             4.80

 server_secret                        string*         unset         cram_md5          3.10
 server_secret                        string*         unset         cram_md5          3.10

-server_service                       string          "smtp"        cyrus_sasl        4.43
+server_service                       string          "smtp"  cyrus_sasl,gsasl,heimdal_gssapi  (cyrus-only) 4.80 (others)

 server_set_id                        string*         unset         authenticators    3.10
 shadow_condition                     string*         unset         transports
 shadow_transport                     string          unset         transports
 server_set_id                        string*         unset         authenticators    3.10
 shadow_condition                     string*         unset         transports
 shadow_transport                     string          unset         transports


@@ -542,13 +561,17 @@ timezone                             string          +             main
 tls_advertise_hosts                  host list       *             main              3.20
 tls_certificate                      string*         unset         main              3.20
                                                      unset         smtp              3.20
 tls_advertise_hosts                  host list       *             main              3.20
 tls_certificate                      string*         unset         main              3.20
                                                      unset         smtp              3.20

+tls_dh_max_bits                      integer         2236          main              4.80
+tls_dh_min_bits                      integer         1024          smtp              4.82

 tls_dhparam                          string*         unset         main              3.20
 tls_dhparam                          string*         unset         main              3.20

+tls_ocsp_file                        string*         unset         main              4.80 if experimental_ocsp

 tls_on_connect_ports                 string          unset         main              4.43
 tls_privatekey                       string*         unset         main              3.20
                                                      unset         smtp              3.20
 tls_remember_emstp                   boolean         false         main              4.21
 tls_require_ciphers                  string*         unset         smtp              4.00 replaces tls_verify_ciphers
                                      string*         unset         main              4.33
 tls_on_connect_ports                 string          unset         main              4.43
 tls_privatekey                       string*         unset         main              3.20
                                                      unset         smtp              3.20
 tls_remember_emstp                   boolean         false         main              4.21
 tls_require_ciphers                  string*         unset         smtp              4.00 replaces tls_verify_ciphers
                                      string*         unset         main              4.33

+tls_sni                              string*         unset         main              4.80

 tls_tempfail_tryclear                boolean         true          smtp              4.05
 tls_try_verify_hosts                 host list       unset         main              4.00
 tls_verify_certificates              string*         unset         main              3.20
 tls_tempfail_tryclear                boolean         true          smtp              4.05
 tls_try_verify_hosts                 host list       unset         main              4.00
 tls_verify_certificates              string*         unset         main              3.20


@@ -616,6 +639,7 @@ provide compatibility with Sendmail.
 -bh              Test incoming SMTP call, omitting callouts
 -bhc             Test incoming SMTP call, with callouts
 -bi            * Run <command>bi_command</command>
 -bh              Test incoming SMTP call, omitting callouts
 -bhc             Test incoming SMTP call, with callouts
 -bi            * Run <command>bi_command</command>

+-bI:help         Show list of accepted -bI:<tag> options

 -bm              Accept message on standard input
 -bmalware      + Invoke configured malware scanning against supplied filename
 -bnq             Don't qualify addresses in locally submitted messages
 -bm              Accept message on standard input
 -bmalware      + Invoke configured malware scanning against supplied filename
 -bnq             Don't qualify addresses in locally submitted messages


@@ -635,6 +659,7 @@ provide compatibility with Sendmail.
 -bV              Verify version number
 -bv              Test recipient address verification
 -bvs             Test sender address verification
 -bV              Verify version number
 -bv              Test recipient address verification
 -bvs             Test sender address verification

+-bw            + Inetd wait mode

 -C             + Use alternate configuration file
 -D             + Define macro for configuration file
 -d             + Turn on debugging output
 -C             + Use alternate configuration file
 -D             + Define macro for configuration file
 -d             + Turn on debugging output


@@ -691,6 +716,7 @@ provide compatibility with Sendmail.
 -oMai          # Supply authenticated id
 -oMas          # Supply authenticated sender
 -oMi           # Supply interface address
 -oMai          # Supply authenticated id
 -oMas          # Supply authenticated sender
 -oMi           # Supply interface address

+-oMm           # Supply message reference

 -oMr           # Supply protocol name
 -oMs           # Supply host name
 -oMt           # Supply ident string
 -oMr           # Supply protocol name
 -oMs           # Supply host name
 -oMt           # Supply ident string


@@ -737,9 +763,12 @@ provide compatibility with Sendmail.
 3. BUILD TIME OPTIONS FOR EXIM
 ------------------------------
 
 3. BUILD TIME OPTIONS FOR EXIM
 ------------------------------
 

-The table below contains a complete list of options that can be set in
-Local/Makefile when building Exim. More information about individual options
-can be found in src/EDITME and OS/Makefile-Default.
+The table below contains a "mostly" complete list of options that can be
+set in Local/Makefile when building Exim.  The only items not included are
+those whose names can be trivially derived from rules stated below.
+
+More information about individual options can be found in src/EDITME and
+OS/Makefile-Default.

 
 The second column below gives the type of option:
 
 
 The second column below gives the type of option:
 


@@ -769,6 +798,23 @@ empty by default, and is provided for just this reason. Of course, if you do
 actually want to modify a setting from the OS-specific file, there is nothing
 to stop you overriding it in your Local/Makefile.
 
 actually want to modify a setting from the OS-specific file, there is nothing
 to stop you overriding it in your Local/Makefile.
 

+When building Exim with dynamically loaded lookup support, for "LOOKUP_FOO",
+you can define "LOOKUP_FOO_INCLUDE" and "LOOKUP_FOO_LIBS", for includes and
+libraries specific only to that module.  These rules are only used where the
+relevant lookup is a module.  These options are not explicitly listed below.
+
+Variables with names endined `_PC' are used for pkg-config integration; setting
+the value to the name of a pkg-config package will cause Exim's build system to
+query the --cflags and --libs for the given name, when building anything
+dependent upon the component associated with the `_PC' variable.  For lookups,
+if the lookup is dynamically loaded, then this *replaces* the use of the
+corresponding _INCLUDE and _LIBS options, which will be ignored.  If the lookup
+is statically loaded into Exim, the results will be inserted into the
+"LOOKUP_INCLUDE" and "LOOKUP_LIBS" options.  For authenticator, the results
+will be inserted into the "CFLAGS" and "AUTH_LIBS" options.  These options are
+only listed below for the TLS implementation cases.
+
+

 Option                       Type         Description
 ------------------------------------------------------------------------------
 
 Option                       Type         Description
 ------------------------------------------------------------------------------
 


@@ -779,6 +825,9 @@ APPENDFILE_LOCKFILE_MODE     optional*
 AR                           system       command to build a library
 AUTH_CRAM_MD5                driver       include cram_md5 authenticator
 AUTH_CYRUS_SASL              driver       include Cyrus SASL authenticator
 AR                           system       command to build a library
 AUTH_CRAM_MD5                driver       include cram_md5 authenticator
 AUTH_CYRUS_SASL              driver       include Cyrus SASL authenticator

+AUTH_GSASL                   driver       include GNU SASL authenticator
+AUTH_HEIMDAL_GSSAPI          driver       include Heimdal GSSAPI authenticator
+AUTH_LIBS                    system       library linkage for authenticators

 AUTH_PLAINTEXT               driver       include plaintext authenticator
 AUTH_SPA                     driver       include SPA (NTLM) authenticator
 AUTH_VARS=3                  optional*    number of $auth variables
 AUTH_PLAINTEXT               driver       include plaintext authenticator
 AUTH_SPA                     driver       include SPA (NTLM) authenticator
 AUTH_VARS=3                  optional*    number of $auth variables


@@ -807,6 +856,7 @@ DEFAULT_CRYPT                optional     default crypt() function
 DELIVER_IN_BUFFER_SIZE       optional*
 DELIVER_OUT_BUFFER_SIZE      optional*
 DISABLE_DKIM                 optional     disables DKIM support
 DELIVER_IN_BUFFER_SIZE       optional*
 DELIVER_OUT_BUFFER_SIZE      optional*
 DISABLE_DKIM                 optional     disables DKIM support

+DISABLE_DNSSEC               optional     disables attempts to use DNSSEC

 DISABLE_D_OPTION             optional     disables -D option
 ERRNO_QUOTA                  optional*    error code for system quota failures
 EXICYCLOG_MAX                optional     number of old log files to keep
 DISABLE_D_OPTION             optional     disables -D option
 ERRNO_QUOTA                  optional*    error code for system quota failures
 EXICYCLOG_MAX                optional     number of old log files to keep


@@ -820,11 +870,12 @@ EXIM_MONITOR                 optional     set to eximon.bin to compile
 EXIM_PERL                    optional
 EXIM_USER                    mandatory    user to use for Exim
 EXIWHAT_EGREP_ARG            system**     to find Exim processes from ps
 EXIM_PERL                    optional
 EXIM_USER                    mandatory    user to use for Exim
 EXIWHAT_EGREP_ARG            system**     to find Exim processes from ps

-EXIWHAT_KILL_SIGNAL          system**     -SIGUSER1 or numerical equivalent
+EXIWHAT_KILL_SIGNAL          system**     -SIGUSR1 or numerical equivalent

 EXIWHAT_MULTIKILL_CMD        system**
 EXIWHAT_MULTIKILL_ARG        system**
 EXIWHAT_PS_ARG               system**     to list all processes
 EXIWHAT_PS_CMD               system**     path to ps command
 EXIWHAT_MULTIKILL_CMD        system**
 EXIWHAT_MULTIKILL_ARG        system**
 EXIWHAT_PS_ARG               system**     to list all processes
 EXIWHAT_PS_CMD               system**     path to ps command

+EXPAND_LISTMATCH_RHS         optional*    restore pre-4.77 match_*{}{} behaviour

 EXTRALIBS                    system       additional libraries
 EXTRALIBS_EXIM               system       additional libraries for Exim only
 EXTRALIBS_EXIMON             system       additional libraries for the monitor
 EXTRALIBS                    system       additional libraries
 EXTRALIBS_EXIM               system       additional libraries for Exim only
 EXTRALIBS_EXIMON             system       additional libraries for the monitor


@@ -879,7 +930,8 @@ MAX_INTERFACES               system       maximum network interfaces
 MSGLOG_DIRECTORY_MODE        optional*    mode for message log directory
 MV_COMMAND                   system       path to mv command
 NO_SYMLINK                   optional     install doesn't make 'exim" symlink
 MSGLOG_DIRECTORY_MODE        optional*    mode for message log directory
 MV_COMMAND                   system       path to mv command
 NO_SYMLINK                   optional     install doesn't make 'exim" symlink

-PCRE_CFLAGS                  system       compile flags for PCRE library
+PCRE_CONFIG                  system*      use pcre-config for PCRE support
+PCRE_LIBS                    system*      library for using PCRE

 PERL_CC                      system*      compiler for Perl interface code
 PERL_CCOPTS                  system*      flags for same
 PERL_COMMAND                 system       path to Perl
 PERL_CC                      system*      compiler for Perl interface code
 PERL_CCOPTS                  system*      flags for same
 PERL_COMMAND                 system       path to Perl


@@ -917,7 +969,7 @@ TCP_WRAPPERS_DAEMON_NAME     system*      daemon name used by tcpwrappers librar
 TIMEZONE_DEFAULT             optional     default for timezone option
 TLS_INCLUDE                  optional     path to include files for TLS
 TLS_LIBS                     optional     additional libraries for TLS
 TIMEZONE_DEFAULT             optional     default for timezone option
 TLS_INCLUDE                  optional     path to include files for TLS
 TLS_LIBS                     optional     additional libraries for TLS

-TMPDIR                       system       value for TMPDIR environment variable
+EXIM_TMPDIR                  system       value for TMPDIR environment variable

 TRANSPORT_APPENDFILE         driver       include appendfile transport
 TRANSPORT_AUTOREPLY          driver       include autoreply transport
 TRANSPORT_LMTP               driver       include lmtp transport
 TRANSPORT_APPENDFILE         driver       include appendfile transport
 TRANSPORT_AUTOREPLY          driver       include autoreply transport
 TRANSPORT_LMTP               driver       include lmtp transport


@@ -926,6 +978,8 @@ TRANSPORT_SMTP               driver       include smtp transport
 TRUSTED_CONFIG_LIST          optional     config files safe to retain privileges
 USE_DB                       system**     use native DB interface
 USE_GNUTLS                   optional     use GnuTLS instead of OpenSSL
 TRUSTED_CONFIG_LIST          optional     config files safe to retain privileges
 USE_DB                       system**     use native DB interface
 USE_GNUTLS                   optional     use GnuTLS instead of OpenSSL

+USE_GNUTLS_PC                optional     probably "gnutls"
+USE_OPENSSL_PC               optional     probably "openssl"

 USE_READLINE                 optional     try to load libreadline for -be
 USE_TCP_WRAPPERS             system       link with tcpwrappers
 USE_TDB                      optional     use the tdb DB interface
 USE_READLINE                 optional     try to load libreadline for -be
 USE_TCP_WRAPPERS             system       link with tcpwrappers
 USE_TDB                      optional     use the tdb DB interface